Gambling with Our Public Lands
The Scientific Uncertainty and Fiscal Waste of BLM’s Vegetation Removal Program in the West
Every year, the Bureau of Land Management (BLM) spends tens of millions of taxpayer dollars destroying hundreds of thousands of acres of native pinyon pine and juniper forests and sagebrush stands throughout the West.
These vegetation removal projects – typically done in the name of habitat and watershed “restoration” – are devastating public lands. Yet there is little evidence to support the BLM’s assertion that these projects improve forage or habitat for wildlife, or reduce stream erosion and runoff.
In fact, scientific evidence often counters the claims made by proponents of vegetation treatments on public lands
A 2019 report released by Wild Utah Project – a Utah-based non-profit organization focused on conservation science – analyzed the existing scientific literature on mechanical vegetation removal projects in western pinyon-juniper and sagebrush communities to determine the state of current science and identify gaps in understanding regarding these potentially harmful projects. (Click here to view the report (opens in PDF).)
The scientific analysis raises important questions as to why the BLM is gambling taxpayer money to destroy native landscapes on our public lands.
What is a Vegetation Removal Project?
Bad Odds, Bad Returns
A Slippery Slope for Wildlife
While improvement of wildlife habitat is often a primary rationale for vegetation removal in both pinyon-juniper and sagebrush communities, existing science shows that the results of these projects are uncertain at best.
Half of the existing data points regarding the effect of vegetation removal on wildlife in sagebrush habitat show either a negative impact or “no significant effect.” For projects in pinyon-juniper woodlands, the report states that “the general trend across studies was for non-significant results of mechanical removal.”
One exception to the “non-significant results” trend was a negative impact to bird species that require pinyon-juniper habitat, such as the pinyon jay. The report notes that managing wildlife habitat is extremely complex and that “what benefits one species may be a detriment to another. . . . This argues against large expanses being treated with one method that creates a single homogenized vegetation community.”
Better Ways to Restore Watershed Health
Watershed restoration is often touted as a secondary benefit to vegetation removal. While the report notes that myriad individual factors of a particular project area influence a project’s benefit or detriment to ground water recharge (e.g., elevation; vegetation type; and timing, amount, and type of precipitation), existing scientific reviews “have concluded that treatments do not reliably increase water yield on a watershed scale, although water availability may increase in local areas.”
Mechanical treatments disturb soils, which often leads to an increase in erosion, especially in places that rely on biological soil crusts as a component of soil stability.
Of the studies reviewed in the report, only 4% to 7% showed treatments decrease runoff and erosion. The report concludes that hand thinning of vegetation is the least disruptive method of treatment to soils.
A Gamble in Need of Reform
Scientific Recommendations and Conclusions
The Wild Utah Project report makes the following findings and recommendations:
The Wild Utah Project report illustrates the need for policy reform of the BLM’s vegetation removal program. SUWA suggests the BLM adopt the following guidelines for vegetation removal projects:
- Implement the least intensive, lowest risk actions first, leaving all surface-disturbing activities as a last resort. Low risk/low cost actions include removing cattle from the subject landscape and aerially seeding with native species.
- Align vegetation removal goals with the soil type of the area. For example, the BLM often argues that pinyon-juniper is “encroaching” into sagebrush habitat, but if the soil type shows that it is expected to be a pinyon-juniper forest, then the project lacks a scientific basis. Similarly, if the project area contains old-growth pinyon-juniper forest, the “encroachment” theory lacks merit.
- Take a precautionary approach to project size. Large-scale vegetation removal should not occur until the BLM develops defensible procedures and methods that ensure a high-likelihood of project success.
- Develop scientifically-robust monitoring protocols and utilize untreated reference areas to ensure that there is a baseline against which results can be compared.
- Include adequate funding for long-term monitoring and development of peer-reviewed scientific literature as part of project proposals. The BLM should partner with the U.S. Geological Survey when possible to assist in long-term monitoring.
- Analyze the impact of vegetation projects on biological soil crust and non-game species dependent on pinyon-juniper forests and sagebrush stands.
- Stop vegetation removal on wilderness-quality lands, including Wilderness Study Areas (WSAs) and BLM-identified lands with wilderness characteristics (LWCs). There are millions of acres of BLM-managed public lands in the West that lack wilderness quality, where the BLM can develop and test methods and strategies for consistently achieving desired results.
- Focus on prior vegetation removal project areas that have failed or underperformed before conducting surface-disturbing activity on previously undisturbed landscapes.
- Define meaningful goals and parameters for vegetation removal projects that define success or failure. Failing to identify specific desired outcomes limits the agency’s and the public’s ability to meaningfully analyze project efficacy.
The BLM should take a careful, scientifically-sound approach to vegetation removal and monitoring, rather than continuing to allow a desire for funding to determine project location and size.